Direct visualization of electrogenic becteria in a microfabricated microbial fuel cell

We report a microfabricated transparent microbial fuel cell (MFC) visualizing electrogenic bacteria in situ with realtime and simultaneous measurements of bacterial electron transfer. The MFC features a protruded anode chamber which can be directly placed under an optical microscope for observing live bacterial behavior. The MFC had 140 μL-sized anode and 70 μL-sized cathode chambers separated by a proton exchange membrane (PEM). Using this device, a maximum current density of 2.3 μA/cm² and power density of 5.29 nW/cm² were achieved. This technique allows for both optical and electrical studies of the electrogenic bacteria and provides valuable information between the cell growth/biofilm formation and the extracellular electron transfer processes associated with MFC operation.